Refrigerator



Dec. 5, l 933.

E. D. CAMPBELL El AL REFRIGERATOR Filed May 23. 195C 3 Sheets-Sheet 2 /TmRA/fy l Dec- 5, 1933 E. D. CAMPBELL Er AL REFRIGERATOR Fiied May 2s. 195o 3 Sheets-Sheet 3 r. l l l l l l l l l ll Patented Dec.' 5, 19733 BEFRIGERTOR tion of Delaware Application May 23, 1930. Serial No.'455,i)32

2 Claims. (Cl. 62-915)` This invention relates generally to refrigerators, and has particular reference to a refrigerated vehicle body.

The body shown in the accompanying drawings is particularly adapted to be mounted on the chassis of a motor vehicle, but obviously this is merely by way of example as the refrigerating system and the construction for .accomplishing the purposes hereinafter to be described may be employed in constructions other than those associated with or forming motor vehicles, for example in railway refrigerator cars and in fact in any chamber to be refrigerated.

The refrigerator of the present invention is designed particularly for the storing and transportation of milk and for meat which is not frozen, and it has been found that temperatures between 32 degrees and 42 degrees F. above zero are satisfactory for this purpose, though commodities other than milk and meat may of course be satisfactorily transported. The construction of the present invention, as' shown in the drawings, has been found, in practice, to result in a refrigerator in which the desired and before mentioned temperatures may be accomplished and maintained.

The present invention makes use of a solidied mass of an inert material which at ordinary pressures and temperatures is a gas, and which, on

absorption of heat passes directly from the solid to the gaseous state without an intermediate liquid stage. An example -of such solidified material is solid carbon dioxide and in the present instance this refrigerant is positioned in a closed container in a chamber to be refrigerated; the container being so arranged as to be in an air current in the chamber whereby the air is cooled.

One object of the present invention is the provision of an air cooled refrigerator.

Another object of the invention is the provision of a refrigerator in which air is distributed and circulated to be cooled by contact with a closed container holding a solidified mass of an inert material.

Still another object of the invention is the provision of a refrigerator, the refrigerant therefor being solid carbon dioxide.

This invention also contemplates the provision of a refrigerator in which air is circulated transverse to the longer dimension of the refrigerator for substantially the full length of the latter, thus avoiding the presence of a warm spot or area Within the refrigerator. This is particularly important in constructions in which side doors are present and the refrigerating apparatus is aring such as to prevent permeation of the chamber by carbon dioxide gas.

A further object of vthis invention is the provision of a refrigerator, cooled by air reduced in temperature by contact with a solid carbondioxide container, the construction of the refrigerator and the solid carbon dioxide container being such as to prevent the. free escape of gas subliming from the solid carbon dioxide, whereby to provide an insulating blanket of carbon dioxide gas around the solid carbon dioxide in the container therefor.

Still another object of this invention is the provision of a new and improved refrigerating system. I

A further object of this invention is the provision of a referigerator using solid carbon dioxide as a refrigerant, and means for effecting circulation or distribution of air in'the refrigerator..

The invention further contemplates a refrigerator construction having closed containing means for the refrigerant adjacent the upper wall thereof wherebyl it is free of the lading, and which containing means are shielded whereby to effect circulation for air about the containing means in order to cool the air.

Another object of the present invention is the provision of a new and improved container for solid carbon dioxide for use in a refrigerator;

Other objects and advantages of this invention will be apparent from the following description taken in conjunction with the accompanying drawings in which:

Fig. 1 is a sectional view through the refrigerator of the present invention, the view b eing taken on the line 1-1, Fig. 2.

Fig. 2 is a top plan View of the refrigerator with the top sheathing and insulation removed; the view having certain parts broken away and other parts shown in section, and

Fig. 3 is a sectional view on the line 3-3 of Fig. 2.

Referring now more particularly to the draw'- ings, A indicates generally the storage chamber or compartment to be refrigerated and in which the commodities to be stored or transported are contained. This chamber is preferably formed of metal, such for example as galvanized iron, and is of a construction more specifically described hereinafter, and is enclosed in a casing B formed of insulating material 2 and a frame composed of suitable stringers 4, and carlins and purlins 6 and 8, respectively. The specific construction of the casing forms no part of the present invention and hence is not described in detail.

Thecasing B is provided with an external metal sheathing 10 and with a metal roof sheathing 12 which overlaps the sheathing 10 as shown at 13. The casing of course is provided with entrance means into the chamber A and in the present instance the casing is shown as being provided with a door 14 formed in one side wall and framed as shown at 16. If desired a door 18 may be provided in the rear end wall of the casing.

The storage chamber A is formed of metal, as before mentioned, and is preferably of a size to nicely t the interior of the casing B. In the present instance, the chamber is formed of con-v nected sheets of metal 20, overlapped as at 22; the overlapping portions being connected in any suitable manner as by welding or riveting. It has been found desirable to so form the chamber A that it is leak proof at the joints of connected sheets and therefore welding has been found highly satisfactory, but obviously the lapped joints may be riveted together with their seams soldered if desired.

At the top of the chamber A, adjacent the side walls of the casing B, and adjacent the ends of the -chamber are positioned closed containers 24 for holding a refrigerant. The refrigerant in -this instance is a solidined mass of an inert material such for example as solid carbon dioxide. As clearly shown in Fig. 1 each of these containers comprises a top 26 connected to the top of the chamber A in any suitable manner as by clips or brackets 27, a. bottom 28 and ends 30. The containers also include front and rear side Walls 32 and 34 respectively as shown more clearly in Fig. 3. Also as shown in Fig. 3 the containers 24v are spaced from the side walls of the casing B. Extending through the containers, from side wall to side wall andA adjacent the end walls of said containers in order not to interfere with the insertion of solid carbon dioxide therein, are tubular air ducts 36 which in- Acline upwardly from the rear walls 34 to the front walls 32. This construction is clearly shown in Fig. 3 and the ducts 36 are formed of metal and have retaining flanges 38 at their ends for an obvious purpose.

The top wall 26 of each container is provided with an opening surrounded by a. flangev 40 which extends into a hatch in the roof of casing B,

which hatch is defined, in part, by framing 42 provided with a metal liner 44 over which the liange 40 extends and to which the latter is connected in any suitable manner as by soldering or welding. The ange 40 is stiffened by suitable braces 46 which are shown more clearly in Fig. 2. In the instance shown the flange 40 is substantially rectangular in shape and the braces 46 are arranged in the corners.l Obviously the flange 40 may be of any desired or preferred shape within theL scope of the present invention. 'Ihe remainder of the hatch is provided with a framing 47 connected tothe framing 42 and provided with a liner 48 the lower end of whichlatter overlaps the upper end of the flange 40 and is connected thereto. The upper end of the liner 48 is flanged over the upper edge of the framing vto the top wall of the chamber A by means of 14::

47 and is then bent downwardly and secured to the roof sheathing as shown at 49. 'Ihe construction just described provides a metal liner for the supplementary framing 47 but within the scope of the present invention a liner of insulat- E ing material may be substituted for the liner 48, thereby providing an arrangement in which heat from the outside will not pass through metal from outside the hatch to the container 24. For closing the hatch suitable covers 51 are provided E which are removable to permit insertion of the refrigerant into the containers 24, and if desired, hatch plugs may be used in the hatches. ,From the description just given, it is apparent that the solid carbon dioxide container is substan- 9 tially closed against inlet of air, and gas formed by sublimation or evaporation of the refrigerant will expel any air from the container 24 and ll the container' around the solidified refrigerant; thus forming an insulating blanket of gas 9 for the said solidified refrigerant and decelerating its sublimation.

As is Well known, warm air will rise, or 1n other words the `cooler the air is, the greater its specic gravity. In the present instance, warm air will rise in the chamber A and will be cooled 4by direct contact with the containers 24 .which are maintained at a .low temperature by the solid y. carbon dioxide. In order to combine features of cold air distribution in the chamber A, and at l0` the same time to provide a construction in which the containers 24' are maintained out of contact with the lading in the chamber A, and further to provide av construction in which the lading is protected against condensation dripping, a 114 shield indicated generally at 50 is arranged along each side of the chamber around th'e containers. The shield is employed also for the purpose `of varying the passage of air to the containers 24 whereby to control the temperature in chamber 11.I A. It will be apparent that the shields just described provide conduits arranged adjacent each side wall of the refrigerator or the vehicle body as the case may be which provide for circulation of air; the conduits thus being air conduits.

The chamber A is of course provided With openings alined with the`door openings in the casing B, and the chamber A is connected at the door openings, tothe casing B in such a manner as to prevent leakage of air between the chamber A 3125 and .the casing B. This is accomplished by the connection of the material of the chamber A to the door framing and may assume any preferred or desired construction. In the present instance the casing Bis shown as being provided with a 13,( side door, therefore the shield 50 at this side of the chamber is not continuous from end to end of the chamber but the shield 50 on the opposite side of the chamber is shown as continuous from end to end of the chamber A. This construction 13C is clearly indicated in Fig. 2.

The shield is more clearly shown in detail in` Fig. 3 ,and comprises a metal sheet bent to form a front wall 54 and a bottom wall 56; the `ends of said Walls being provided with ilanges 58 (ses Fig. 1) whereby to secure theshield to the end walls of the chamber A. 'Ihe upper edge of the front wall 54 is flanged as at 60 and is secured suitable fasteners such as the screws 62 which pass into the purlins 8. The lower edge o1' each o1' the sheets is downwardly anged as shown at 64 and secured to the adjacent side wall of the chamber A. For stiffening the sheets at the .LJU

bends, plates 66 are employed which are riveted as at 68 to the sheets. y

The containers 24 in the chamber A adjacent the side wall in which the door opening 14 is formed are provided with individual shields of substantially the same form as hereinbefore described but the shield for said containers is not continuous from end to end of the chamber, as before mentioned, and adjacent the door opening, the shields are provided with ends 70 the upper edges of which are flanged' at 72 and secured to the top or roof of the chamber A; the ends 70 extending from the front wall 54 of the sheet to the side wall of the chamber A and being secured to the latter.

As clearly shown in the drawings .the shields are spaced from th'e containers 24 to provide a space 74 about the containers 24 for the passage of air around the containers. Adjacent the containers 24, the shields 50 are provided with elongated openings 76 each having a damper or shutter 77 therein supported for pivotal movement on a shaft 78 mounted in brackets 80 secured to the shields 50. One end of each of the shafts' 78 is bent as shown at 82 to form a crank by which the damper may be actuated to vary the' position thereof in the opening 76 whereby to vary the effective area of the opening as will be apparent.

The dampers may be connected in such amanner as to be actuated by a temperature'responsive device such as is well known in the art, or the dampers may be operated manually. Inasmuch as the specific operating means for the dampers forms no part of the present invention the same is not' illustrated. l

The damper, as just mentioned, controls the extent or effective area'of the opening 76 and this, obviously, controls the admission of air into the space 74 between the shield 50 and the containers 24. The warm air rising will pass into the spaces 74 through the openings 76, in an amount and at a rate dependent upon the position of the dampers 77 and said air will be cooled by contact with the walls of the containers. Some of the air passing through these openings 76 will also enter the ducts 36 and be cooled, and the cooled air will pass from the spaces 74 into the chamber A through suitable openings 88 formed in the bottom wall 56 of the shields.

From the above description it is believed that the construction of the present invention will be fully apparent to those skilled in the art. The present invention provides for distribution and circulation of air within the chamber A whereby to refrigerate the chamber and maintain the latter at a predetermined temperature. When solid carbon dioxide is in the containers 24, it will be apparent that the containers are maintained at a low temperature. The warm air in the chamber A will rise and enter the space between the shields 50 and the containers 24 and be cooled and then pass out through the openings 88 into the chamber A; the cooled air dropping and then absorbing heat and rising again to be recooled and recycled. Because of the arrangement of the air conduits longitudinally within the body it will be apparent that the air is circulated in a transverse direction relative to the longer dimension of the body; this resulting in a system f m which the whole interior of the body is refrigerated and a warm area is avoided.

Containers 24 for the solid carbon dioxide are so formed as to prevent escape of gassubliming from the solid carbon dioxide into the chamber A. The hatch covers 51` close the hatches and hence the containers 24 against the free escape of carbon dioxide gas to the atmosphere, though the gas is not totally prevented from escaping to the atmosphere as it will leak out through the joints effected between the hatch covers and the liners 48. The gas which sublimes from the solid carbon dioxide is therefore not vented immediately to the atmosphere, and in fact the escape of gas to the atmosphere is retarded by reason of the covers 51. This retardation of the escape of the gas permits the gas to flll the containers 24 about the solid carbon dioxide and thus provide an insulating blanket of gas around the'solid carbon dioxide which retards the subliming of said solid carbon dioxide and yet, because the carbon dioxide gas is at an extremely low temperature, provides for thecooling of the containers 24 and their retention at a low temperature, or at a temperature sufficient to cool the air passing through the opening 76 to a degree sufficient to afford proper refrigeration of the chamber A and retention of such proper temperature in the chamber A whereby to maintain commodities in the chamber A at a desired temperature.

The containers for the solid carbon dioxide are uninsulated and obviously the solid carbon dioxide therein is at all times in direct heat exchange relation with the interior of the chamber A through the metal walls of said containers, this construction providing for the cooling of air which passes into the -air passage 74 by direct contact with the outer surfaces of the refrigerj ant holding containers. IThe carbon dioxide gas does not permeate the chamber A and the refrigeration system of the present invention is strictly an air cooling system. This is in contradistinction to any system in which carbon dioxide gas is permitted to escape into a chamber to be refrigerated, in which system the carbon dioxide gas causes the exclusion of air from the chamber to be refrigerated and the refrigerating eiect depends either partially or entirely upon the temperature of the carbon dioxide gas.

The drawings herein illustrate one embodiment of the invention but it is to be understood that the drawings are for illustrative purposes only and various changes in the form and proportions of the construction illustrated may be made within the scope of the appended claims without departing from the spirit of the invention.

What is claimed is:

1.In a refrigerator, a chamber to be refrigerated having side walls and a roof, an air conduit formed between a side wall and the roof, air inlet and outlet means in said conduit, closed longitudinally spaced refrigerant holding containers depending from said roof within said conduit and each being provided with an air duct extending through opposite walls thereof, said duct being inclined downwardly from adjacent said inlet to adjacent said outlet means.

2. Arefrigerator comprising a chamber to be 

